Loudness Revisited: Going into the Calculation Procedures

The paper goes beyond the conventional way of looking at Loudness. We go into the calculation procedures taking into consideration two methods coming from the work of two researchers: Zwicker and Stevens. These methods are described in ISO 532. Instead of going to the traditional way of comparing the overall noises we penetrate in the calculation processes, step by step, getting subsidies to analyze the contributions of each frequency band. We applied the two methods using some random sound pressure spectra we generated. We are able to compare the total Loudnesses in both methods using a least-square fit with linear approximation. The spectra of contributions in sones in third-octave bands are also compared for both methods, through the development of simple mathematical expressions which are able to identify the parcel correspondent to each third-octave band. With the results obtained we discuss some questions like:how close are the overall noises; how masking effects are incorporated and how similar are the band contribution spectra.